Evaluation of atmospheric galvanic aluminum corrosion in electrical transmission towers at different sites in the Valparaíso region, Chile. Wire‐on‐Bolt Test (CLIMAT)

Abstract

This study evaluates environmental aggressiveness and atmospheric galvanic corrosivity categories in Chile (Classification of Industrial and Marine ATmospheres test) by installing bolts in electrical transmission towers in the Valparaiso region across four exposure sites: Playa Ancha, San Sebastián, Las Vegas, and San Felipe. Classifications of marine corrosion index (MCI), industrial corrosion index (ICI), and atmospheric corrosion index (ACI) used different galvanic couples: aluminum/steel for MCI, aluminum/copper for ICI, and aluminum/polyethylene for ACI. Corrosion indices varied by season (summer, autumn, winter, and spring), for which couples were exchanged every 3 months. Intraseason variation depended mainly on the meteorochemical variables of the zone, the Cl−/SO2 ratio, and the presence of general and pitting corrosion in the aluminum. The results indicate that, regardless of environmental condition, the aluminum in Al/steel (MCI) and Al/copper (ICI) couples presented a higher corrosion rate than when not forming a galvanic couple (ACI). Moreover, under higher environmental chloride, these differences increase. The Playa Ancha station presented the highest ACI.

Evaluation in Real Conditions of New Anticorrosive Formulations Based on Polyphenols from Natural Sources and Encapsulated Nanoparticles

“…The sum of the partial wetting times constitutes the so-called time of wetting, during which corrosion is possible. To calculate the wetting time, RH ≥ 80% and temperature above 0 • C were used as the critical value, as indicated by ISO 9223 [6,[31][32][33]. The meteorochemical characterization was carried out on a quarterly basis, recording the deposition rates of the main corrosive agents, sulfur dioxide, and chlorides, based on ISO 9225 standards.…”

Experimental Study on Neutral Salt Spray Accelerated Corrosion of Metal Protective Coatings for Power-Transmission and Transformation Equipment

“…Li et al [6] showed that long-term high temperature, 2 of 18 humidity and salinity could significantly promote the corrosion of metal materials in equipment. Valverde et al [7] found that the transmission towers in power equipment were more prone to atmospheric corrosion if they were in an atmospheric environment for a long time. Wang et al [8] found that the corrosion of Cl − in atmosphere brought more serious corrosion damage to metals and even affected their service life.…”